1,986 research outputs found
Pesticide Residues: Inorganic and Other Metal-Containing Compounds
No full textInorganic and organometallic compounds have been used as pesticides. At present, in most developed countries, only copper compounds are used in significant amount as fungicides. The others have been banned for either toxicological or environmental reasons. It is believed that some organotins are still used in some developing countries. Copper compounds, if used as directed, do not pose health risks. However, the estimated long-term intake in the European Union is not much below the acceptable daily intake, when other nonpesticidal sources of copper are considered. Organotins have a nonnegligible acute toxicity. Also, triphenyltin has immunotoxic and, possible, carcinogenic effects, and cyhexatin/azocyclotin have embryotoxic properties. However, estimated intakes are below reference values
Exposure assessment for the chemical and physical agents
No full textExposure assessment to either chemical or physical agents, as applicable, is a necessary step for both etiologic diagnosis of occupational disease and health surveillance of workers. The assessment can be carried out by measurements of concentrations in air of the substance by either fixed or personal samplers. The former give an indication of the general environment, the latter, applied near the mouth of the worker, provide personalized information. Dermal exposure (deposition) and absorption occur in the occupational setting, but their measurement is so complex that there are no routine methods and no exposure limits established. Oral exposure is accidental or associated with poor hygienic practices, is very difficult to assess, and there are no occupational exposure limits of oral intake. Also accidental injuries caused by needles or other sharp objects that might be contaminated by chemicals occur but exposure assessment in this condition is almost impossible. Exposure is also assessed by biologic monitoring that entails measurements of the substance and/or of its metabolite(s) in accessible fluids, generally urine, blood, or expired air. Biochemical changes, e.g., enzyme inhibition, associated with exposure are also measured. The results of these measurements are compared with existing limit values in order to conclude on the safety of the working conditions. Since the limit values are derived with the application of conservative assumptions, there are no fine lines between health and disease. Therefore, in the clinical setting values below the limit can be generally regarded as safe. Values above the limits should be considered in conjunction with all other information to judge on the likelihood that the disease under investigation may have been caused by exposure to the substance
Calcolo del valore dell'usufrutto vitalizio; l'infondatezza dei coefficienti "ministeriali"
No full textL'articolo ha l'obiettivo di dimostrare come la determinazione dei coefficienti per calcolare il valore dell'usufrutto, finora effettuata dall'amministrazione finanziaria, non abbia tenuto conto dell'aspetto attuariale. Pertanto si contesta la correttezza e la coerenza dei coefficienti di calcolo del valore dell'usufrutto presenti nella tabella ministeriale rispetto a quelli che invece si ottengono seguendo una valutazione che sia non solo di carattere finanziario ma anche di natura attuariale
Genotoxicity in risk assessment : is it time to use a threshold approach?
No full textSubstances that act via a genotoxic mechanism are considered to follow a low dose linear relationship with the absence of a threshold. The discussion on the existence of a threshold for genotoxic (mutagenic and clastogenic) compounds appears sometimes more an academic exercise than of practical use in public health. However, pragmatically, determination of the PoD, i.e. the dose/concentration from which we derive acceptable exposure levels, should be the goal. This will include appropriate dose response data analysis, with statistically defensible methods and use of mechanistic data, and application of adequate uncertainty factors. The best and full use of the quantitative information can be used to analyse dose–response data, and dismiss the binary classification scheme for use in risk assessment and management. Certainly, in areas such as the relationship between the genotoxic and the carcinogenic effect, the appropriate BenchMark Response (BMR) to be used, the relation between effects in target tissues vs those observed in surrogate tissues, and the uncertainty of our measurements there is a need of more solid data. While the simple binary classification scheme can be of some help for screening and prioritization of substances that need further scrutiny, it is not an adequate tool to be used for risk management decisions. The final step of the assessment for guiding management decisions should be quantitative to the extent possible. Accepting the threshold approach on which to base the risk management decisions has significant beneficial economic and societal impact and implications
Risk assessment of mixtures in the food chain
No full textMany chemicals are present in food as a result of involuntary contamination or resulting from voluntary addition, for example,
pesticide or veterinary drug residues, or additives. Assessment of the health risk associated with combined exposure to multiple
chemicals from food presents many issues. From the toxicological side, the main question is the identification of the compounds
to include in a group for which to assess combined risk. Different criteria have been developed that resulted in groups of compounds of different sizes. Intake can be assessed with increasing levels of refinement, which require increasing levels of resources, in order to identify the occurrence of combined exposures. Assessments have been carried out so far for a number of groups of pesticide residues which resulted in estimated intakes that did not raise concern. However, there is a need for international harmonization of methodologies, especially in those fields where international food trade is involved
Per Angelo Trevisani ritrattista
No full textIl saggio rende nota un'effigie realizzata dal pittore veneziano Angelo Trevisani, elogiato da Anton Maria Zanetti (1733) per la sue doti ritrattistiche. L'opera in esame, datante al 1723-1724, raffigura il procuratore di San Marco Giovanni Emo; in precedenza, recava un'attribuzione a Fortunato Pasquett
The relationship between isofenphos cholinergic toxicity and the development of polyneuropathy in hens and humans
No full textSpecies differences have been observed between hen and human clinical manifestations of isofenphos toxicities. Hens treated with the insecticide isofenphos (90 mg/kg p.o.) developed severe cholinergic toxicity followed by mild organophosphate-induced delayed polyneuropathy (OPIDP). However, a patient developed severe OPIDP, which was preceded by very mild cholinergic signs, after an attempted suicide with a commercial formulation containing isofenphos and phoxim, an insecticide not causing OPIDP (estimated doses were 500 and 125 mg/kg, respectively). To explain this difference the following hypotheses were tested: (1) phoxim is a promoter of isofenphos-induced OPIDP; (2) whereas neuropathy target esterase (NTE) is thought to be the target of OPIDP, activation of isofenphos by liver microsomes causes the formation of more potent NTE inhibitor(s) in humans than in hens; (3) in contrast to hen NTE, the sensitivity of the human enzyme to such inhibitor(s) is higher than that of acetylcholinesterase (AChE), the target of cholinergic toxicity. Results showed that phoxim (22.5 mg/kg p.o.) was not a promoter of OPIDP in hens and that the ratio AChE inhibition:NTE inhibition by microsome-activated isofenphos was similar for both hen and human enzymes. The schedule of antidotal treatment in hens is the likely explanation for the observed difference from the patient. Peak AChE inhibition was maintained in hen brain up to 6 days after a single dose of isofenphos, suggesting prolonged pharmacokinetics. However, the AChE reactivator pyridine-2-aldoxime (2-PAM) was given to hens before isofenphos and then every 8 h, whereas continuous 2-PAM infusion was provided to the patient. When 2-PAM was given to hens every hour after isofenphos (90 mg/kg p.o.), the birds remained asymptomatic. Since other organophosphates may have a prolonged pharmacokinetics, testing procedures for the potential of these insecticides to cause OPIDP may underestimate the risk for humans
The history of the Romano famili and "Angelo, tyran de Padoue" by Victor Hugo.
No full textreservedVictor Hugo, nel dramma Angelo, tyran de Padue, ricama tre diverse epoche storiche: i primi decenni dell’Ottocento, a lui contemporanei; la metà del Cinquecento, prescelta per lo svolgimento dell’azione drammatica; il tardo Medioevo evinto dai personaggi principali che compongono il racconto. Tuttavia, l’interesse storico e prettamente romantico verso il periodo medievale assume in quest’opera una rilevanza primaria. Tra le tante casate del nord Italia nominate dall’autore nell’opera, una su tutte sembra essere davvero simbolica. Particolarmente interessante è stato comprendere come la storia della famiglia da Romano costituisca il fulcro della costruzione drammaturgica. Ezzelino III e Cunizza da Romano sono elevati a emblema della poetica romantica e divengono funzionali al messaggio politico e sociale dell’autore.Victor Hugo, in his play Angelo, tyran de Padue, embroiders three different historical epochs: the first decades of the 19th century, contemporary with him; the middle of the 16th century, chosen for the unfolding of the dramatic action; and the late Middle Ages evoked by the main characters in the story. However, the historical and purely romantic interest in the medieval period takes on primary importance in this work. Of the many northern Italian lineages named by the author in the work, one in particular seems to be truly symbolic. It was particularly interesting to understand how the history of the da Romano family forms the core of the dramaturgical construction. Ezzelino III and Cunizza da Romano are elevated to emblems of romantic poetics and become functional to the author's political and social message
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